The present invention relates to swivel joints used to join tubular conduits and, more particularly, to such swivel joints which can be disassembled and assembled quickly and conveniently.
Hoses, tubes, and the like have many uses. In those situations where they extend for some length so that the user at one end is some distance from the other, the manipulations by the user at that one end can lead to twists occurring in such conduits.
One situation in which this occurs is in the use of milking machines In FIG. 1, a milking machine system is partially shown with its milking machine claw, 10, having the usual teat cups, 11. The claw is connected to a flexible milk line, 12, (partially shown by dashed lines in a section, 12', ignoring an alternative path, 12", for now) leading to a pipeline, 13, typically installed permanently in a barn. Pipeline 13 continues to the milk collection system, 14.
As milking of one cow is completed, claw 10 is transferred from that cow to another. This milking and transferring continues until the completion of the milking of all of the cows present. In such transferrings of claw 10, it is rather easy to introduce twists in milk line 12 as a part of manipulating claw 10 into position on one cow, then removing it and transporting it to the next cow, and again positioning it on that next cow. These operations, carried out over a series of cows, provide opportunities for a significant amount of twisting of line 12 (including 12') to occur unless the operator is quite attentive to this possibility and takes steps to avoid such occurrences.
A sufficient twisting in milk line 12 (including 12') leads to reactive forces in that milk line which will cause claw 10 to pull on its teat cups connected to the teats on one side of a cow's udder with greater force than on those on the other side. The additional force on those teats subjected thereto leads to the milk supply in the udder at the time of milking to become exhausted at these teats more quickly than those on the side of the udder subjected to a lesser tensile force. As a result, the vacuum system in collection system 14, which acts to cause the milking action, continues to draw on the teats on the empty side of the udder while completing the milking of the others on the side not yet emptied.
Such continued applications of vacuum to the teats of the cow at the locations that can no longer supply milk leads to irritation of the tissue in the teats. Such an irritation can lead to an infection of these tissues which in turn leads to an increase in the white cells in the blood in the area of the infected tissues. Such an increase in white cells in the blood at this location leads to an increase in somatic cells being shed into the milk, a situation which can lower the value of the milk since it prevents making of certain milk by-products such as cheese.
Further, such continued application of vacuum to the teats of the cow through which milk can no longer be supplied can damage the sphincter valve in the teat. The vacuum acts to distort the tissue which again can lead to an infection and serious deterioration in the ability of the sphincter valve to operate as it should.
Finally, by having one side of the udder exhaust its milk supply first and then the other, the time to complete milking of a cow is lengthened. Finishing both sides at approximately the same time leads to a shorter milking time per cow.
Thus, there is desired a milking machine arrangement which will avoid these problems despite actions by the operator which would introduce twists into the milk line. Such an arrangement should be economical and have structures which can be inspected and cleaned easily.